Modern washing appliances (e.g., dishwashers) typically include a wash pump assembly and a drain pump assembly. The wash pump assembly can be configured to circulate and/or re-circulate liquid that is used to wash the contents (e.g., dishes) of the washing appliance. The drain pump assembly can be configured to remove liquid (e.g., dirty liquid) from the washing appliance after use. Typically, the power required to run the wash pump assembly can be higher than the power required to run the drain pump assembly. Thus, to avoid damaging the appliance and to meet safety standards, it can be important to identify which assembly is connected to a power source before applying such power.